Antarctic Bottom Water (AABW) occupies the lowest ocean layer in the major part of the Atlantic. Despite the fact that this water has the same origin from the Weddell Sea, thermohaline properties of bottom layers vary strongly in different deep basins. Temperature and salinity increase along the pathways of bottom water propagation is caused by mixing of AABW with the warmer and more saline water in the overlying layers. This mixing strongly intensifies over underwater ridges; in addition, these ridges determine the pathways of bottom water spreading. Thus, the ocean topography plays the most important role in the formation of thermohaline structure of deep basins. In particular, the properties of AABW in the western and eastern parts of the South Atlantic significantly differ from each other. In this paper we compare temperature and salinity structure of the abyssal waters of the Southeast and Southwest Atlantic. We used the results of high spatial resolution modeling and hydrographic measurements for this study. We also simulated the velocity field in the bottom layer of the South Atlantic.
Antarctic Bottom Water, deep-water processes, thermohaline structure, numerical modeling
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